| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
(Received for publication, March 27, 1995; and in revised form, June 20,
1995) Sulfite reductase (SiR) from Escherichia coli has a
Volume 270,
Number 35,
Issue of September 01, pp. 20550-20555, 1995
©1995 by The American Society for Biochemistry and Molecular Biology, Inc.
A NEW MODEL FOR THE PROTEIN STRUCTURE
subunit structure, where is a flavoprotein (SiR-FP) containing both FAD and FMN as
prosthetic groups. It also exhibits a NADPH:flavin oxidoreductase
activity with exogenous riboflavin, FMN, and FAD serving as substrates.
The flavin reductase activity may function during activation of
ribonucleotide reductase or during ferrisiderophore reduction. A
plasmid containing cysJ gene, coding for the subunit,
overexpresses flavin reductase activity by 100-fold, showing that
is the site of free flavin reduction. The overproducer allows a fast
and simple preparation of large amounts of the flavoprotein. Kinetic
studies of its flavin reductase activity demonstrates a ping-pong
bisubstrate-biproduct reaction mechanism. NADP inhibition studies show that both substrates, NADPH and free
flavins, bind to the same site. While the FAD cofactor mediates the
electron transfer between NADPH and free flavins, the FMN cofactor is
not essential since a FMN-depleted SiR-FP retains a large proportion of
activity. In contradiction with previous reports, SiR-FP is found to
contain 1.6-1.7 flavin per
subunit. This result, together
with the sequence homology between SiR-FP and NADPH-cytochrome P-450
reductase, suggests a new model for the structure of the protein with
one FMN and one FAD prosthetic group per subunit.
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
|
|
 |
|
  U. Kirchner, A. H. Westphal, R. Muller, and W. J. H. van Berkel Phenol Hydroxylase from Bacillus thermoglucosidasius A7, a Two-protein Component Monooxygenase with a Dual Role for FAD J. Biol. Chem., November 28, 2003; 278(48): 47545 - 47553. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Filisetti, M. Fontecave, and V. Niviere Mechanism and Substrate Specificity of the Flavin Reductase ActVB from Streptomyces coelicolor J. Biol. Chem., January 3, 2003; 278(1): 296 - 303. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Adak, S. Ghosh, H. M. Abu-Soud, and D. J. Stuehr Role of Reductase Domain Cluster 1 Acidic Residues in Neuronal Nitric-oxide Synthase. CHARACTERIZATION OF THE FMN-FREE ENZYME J. Biol. Chem., August 6, 1999; 274(32): 22313 - 22320. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. Niviere, F. Fieschi, J.-L. Decout, and M. Fontecave The NAD(P)H:Flavin Oxidoreductase from Escherichia coli. EVIDENCE FOR A NEW MODE OF BINDING FOR REDUCED PYRIDINE NUCLEOTIDES J. Biol. Chem., June 25, 1999; 274(26): 18252 - 18260. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. R. Messner and J. A. Imlay The Identification of Primary Sites of Superoxide and Hydrogen Peroxide Formation in the Aerobic Respiratory Chain and Sulfite Reductase Complex of Escherichia coli J. Biol. Chem., April 9, 1999; 274(15): 10119 - 10128. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Gachhui, A. Presta, D. F. Bentley, H. M. Abu-Soud, R. McArthur, G. Brudvig, D. K. Ghosh, and D. J. Stuehr Characterization of the Reductase Domain of Rat Neuronal Nitric Oxide Synthase Generated in the Methylotrophic Yeast Pichia pastoris. CALMODULIN RESPONSE IS COMPLETE WITHIN THE REDUCTASE DOMAIN ITSELF J. Biol. Chem., August 23, 1996; 271(34): 20594 - 20602. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Zeghouf, M. Fontecave, and J. Coves A Simplifed Functional Version of the Escherichia coli Sulfite Reductase J. Biol. Chem., November 22, 2000; 275(48): 37651 - 37656. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| All ASBMB Journals | Molecular and Cellular Proteomics |
| Journal of Lipid Research | ASBMB Today |
